Electrical stimulation of the brain and spinal cord has been used to affect a select number of physiological conditions such as Parkinson's disease, essential tremors, dystonia, chronic pain, and certain psychiatric disorders. Such therapy is often utilized in a subset of the respective patient population that is unresponsive to other forms of therapy, including traditional pharmacotherapy. There are, however, several other autonomic-related diseases such as cardiac, respiratory, renal diseases, and other diseases associated with autonomic function for which a subset of the patient population is also unresponsive to other forms of treatment.
Stimulation of a sympathetic nerve chain, which extends longitudinally along a side of the vertebral column and which includes a chain of sympathetic ganglia, may be used to alleviate the symptoms of these autonomic-related diseases, even though these diseases are not necessarily related to a dysfunction in the sympathetic ganglia. Because sympathetic ganglia have afferent pathways from the central nervous system and efferent pathways to visceral end organs, modulation of sympathetic ganglia may affect both the end organs and the central nervous system. Methods of electrically and/or chemically stimulating the sympathetic ganglia or the sympathetic nerve chain are described in more detail in the inventor's co-pending application 2002/0116030, which is incorporated by reference herein.
Current electrode devices, such as nerve cuff electrodes, however, are not designed in a manner to efficiently effect stimulation to sympathetic ganglia. Therefore, there is an unmet need for a delivery device that effectively provides stimulation to the sympathetic nerve chain to modulate individual sympathetic ganglion as well as multiple sympathetic ganglia.